{"nrhp_refnum":"12000509","name":"Grindstone Island Upper Schoolhouse","other_names":[],"category":"building","location":{"address":"41591 Cross Island Rd.","address_restricted":false,"city":"Clayton","county":"Jefferson County","state":"NY","lat":44.27192512200003,"lon":-76.12879306999997,"geom_source":"nps_gis"},"listed_date":"2012-08-14","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Architecture","Social History"],"significance_levels":["local"],"summary":{"what_it_is":"A one-and-a-half-story frame one-room schoolhouse built in 1885 on Cross Island Road on Grindstone Island, in the St. Lawrence River near Clayton, Jefferson County, New York. A contributing 1885 well pump is on the same parcel.","why_significant":"The nomination argues it is a rare, highly intact nineteenth-century frame schoolhouse in the Town of Clayton, and one of the last operating one-room schools in New York State, in use until 1989. It illustrates how rural districts responded to mid-nineteenth-century school reform and increased funding, and it retains its original setting and community role on an isolated island.","narrative":"Built in 1885, this one-room schoolhouse on Cross Island Road served the upper half of Grindstone Island in the St. Lawrence River, where children could not easily reach mainland schools. The one-and-a-half-story frame building has shingle siding, a standing-seam metal gable roof, 2/2 wood sash windows and a foundation of local pinkish granite. Inside are a vestibule, an open classroom and a small teacher's apartment. A shed-roofed addition with bathrooms was added in 1960, when the island's two schools merged and this one became the only school. A hand-pumped stone well on the grounds supplied water to much of the island. The school taught island children until 1989, making it one of the last one-room schools operating in New York State. It is valued as a rare, well-preserved example of a rural schoolhouse and for its unchanged rural setting. Since 1998 it has housed a heritage center that hosts exhibits, research and community suppers.","period_of_significance":"1885-1962","architect_builder":null,"architectural_style":"Mid-19th Century (vernacular)","criteria":["A","C"],"status_note":"Closed as a school in 1989, restored over the following nine years, and since 1998 used as the Grindstone Island Research & Heritage Center, a museum and community gathering space.","vacant_flag":false,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:50:47.996073-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/lz/electronic-records/rg-079/NPS_NY/12000509.pdf"},"photo":null,"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/75318239","wikipedia":"https://en.wikipedia.org/wiki/Grindstone_Island_Upper_Schoolhouse","wikidata":"https://www.wikidata.org/wiki/Q23091725"},"indexable":true,"url":"https://nationalhistoricalregister.com/new-york/jefferson-county/grindstone-island-upper-schoolhouse-12000509/"}